Here’s a scoop: Every politician’s bunker has a playbook for what to do when prosecutors are closing in. A guide for scoundrels, it advises how to aggressively assert your innocence while saying as little as possible. If necessary, make a minor concession, then stop answering questions and look busy as hell doing your job while privately setting up a legal defense.

Welcome to Mayor Putz’s predicament.

With the corruption scandal expanding, this passage from yesterday’s Post captures a double standard and the mayor throwing a small bone to the wolves: “Four top police officials have already been disciplined as part of the long-running investigation — and Mayor de Blasio has vowed to return the $9,900 Rechnitz and Reichnitz’s wife donated to his 2013 campaign.”

Oh, and the boss says that if there is anything wrong, it’s the system’s fault, not his. Then he declares he won’t answer any more questions on the topic.

A scoundrel’s playbook in action.

Cops are all-too familiar with double standards. They’re usually held to the highest test of integrity while also considered the most expendable in a political crisis. That strikes me as foolishness compounded.

Yet corruption has little to do with fairness and everything to do with power. And to hear de Blasio talk, he is far too big to be held to the same rules as the little people, cops included.

Imagine two white cops putting on the racially charged skit about “C.P. Time” that de Blasio and Hillary Clinton participated in Saturday. Would they have gotten away with de Blasio’s excuse, that “I think people are missing the point here”?

Bet your Black Lives Matter outrage that de Blasio would denounce others for doing what he did, order an investigation and demand an apology. But when he does it, hey, lighten up.

Arrogance isn’t a crime, but it often leads people to think they are above the law and then break it. And arrogance is the defining feature of de Blasio. His “progressive values” give him a license denied to mere mortals.

Before discovering inequality and becoming mayor, he railed against big money in politics, and now he shakes the tree for every dollar on it. It is outrageous when others do it, but he’s different because his “values” are noble.

The sums are staggering. In addition to the $4.36 million he reported raising through three nonprofits he created for no conceivable purpose other than to avoid campaign-finance-law limits, there is a fourth organization that has raked in far more — at least $30 million. That entity, the Mayor’s Fund to Advance New York City, existed before de Blasio took office, with previous mayors raising private money mostly for experimental programs that, if they succeeded, would be put into the city budget.

I’m told de Blasio, after putting wife Chirlane McCray in charge, is using this organization just like the other three he created — as a virtual slush fund where people with business before the city can make unlimited contributions for use at his discretion. I also hear that some people believe they were promised certain government actions in exchange for their contributions.

If that’s true, de Blasio is toast. US Attorney Preet Bharara is zealous about rooting out pay-to-play rot, as he proved with his Albany-shattering convictions of Sheldon Silver and Dean Skelos.

Silver and Skelos, both headed to federal prison, at least tried to keep their scams secret. But many of de Blasio’s public actions certainly look to be part of a quid pro quo. That’s the only way to explain behavior that otherwise looks insane.

The mayor’s feverish push to get rid of carriage horses, after a career of not caring about them, makes no sense — until you realize big donors wanted the horses gone.

Ditto for his war against Uber. The ride-sharing service was popular among New Yorkers, but decidedly unpopular among the fat-cat medallion owners who had ponied up more than $500,000 to de Blasio. The mayor suddenly was foursquare against the riding public.

There’s also a list of strange real-estate and union deals, and there surely are others we don’t know about. Absent better explanations, it is reasonable to conclude the mayor has been corrupted by power.

As for his vow of silence, it won’t be his final word. If he doesn’t defend himself soon, nobody will.

Osama nonsense

A dumb idea from a brilliant man.

Novelist Caleb Carr (“The Alienist”) suggests that killing Osama bin Laden might have been a mistake. He writes that bin Laden was “the one man within the Islamist community” trying to stop groups like the Islamic State from “butchering civilians and other Muslims.”

Good luck trying to sell that to 9/11 families.

Ryan is mispeaker of the house

House Speaker Paul Ryan often resembles a Boy Scout, earnestly trying to do the right thing. But lately, he’s just another confused Republican, careening from mistake to blunder.

His Shermanesque statement yesterday that he will not accept the party’s presidential nomination was necessary only because he had created so much confusion. His many statements about what Republicans stand for and what they will do fueled talk that he was eager to be the nominee if the convention deadlocked.

That would be a disaster, so Ryan was right to say that only those who ran should be considered, adding, “Count me out.”

Consider it done. Now please pipe down and let voters do the talking.

Feds in cheap bank shot

A shakedown and a scam — the settlement between government regulators and Goldman Sachs manages to be both at the same time.

The announcement that Goldman would pay a whopping $5.1 billion to settle charges it misled housing-bond investors during the financial crisis is itself misleading. A compelling New York Times examination shows that Goldman will pay far less than the advertised price.

One analyst said the “fine print” would enable Goldman to reap tax credits and other benefits that could reduce the penalty by 50 to 75 percent. Goldman gets a $1.50 credit for each $1 of loan forgiveness, and money it spends on consumer relief is tax deductible, the Times reports.

The banks were aggressive in marketing bonds with subprime loans, but rating agencies went negligent, most buyers were sophisticated, and the loans themselves were driven by government demands to increase home ownership among low-income buyers.

When the house of cards collapsed, leftist politicians, unable to prove real criminal activity, went after big civil penalties, and banks settled because it was cheaper than going to trial. The settlements also let the pols dole out much of the penalty money to favored groups, which ensures that the pols keep their jobs.